Speaker Fun... Rear Sub is making cracking noise
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Joined: Feb 2018
Posts: 339
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From: Virginia USA
2016 GTs, 2014 C63 AMG and 2014 C350 Sport (wife's car, she thinks it's an AMG - shhhhhh)
Speaker Fun... Rear Sub is making cracking noise
OK, so this is a weird one... I know most of you came here to tell me that it's blown but it is not. It's my wife's car and she is incapable of blowing a speaker... (or anything else for that matter, ahem).
The crackling is pretty intermittent... it will go away for 30 seconds, then come back. Sometimes for a long time, sometimes only for a few seconds.
Here is the odd thing, it happens when I use the fader to push all the power to the fronts speakers AND it happens when the stereo is off completely.
All that leads me to believe it's a short somewhere? Any ideas what/where to start troubleshooting?
The crackling is pretty intermittent... it will go away for 30 seconds, then come back. Sometimes for a long time, sometimes only for a few seconds.
Here is the odd thing, it happens when I use the fader to push all the power to the fronts speakers AND it happens when the stereo is off completely.
All that leads me to believe it's a short somewhere? Any ideas what/where to start troubleshooting?
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12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
Even when you turn it off, the speakers are still used, so the amp isn't really off just the input from the head unit, so a bad speaker could still make noise.
Can you trace it to a speaker or corner of the car, I had one go bad in my 2013 crackling noise, was the center one in the parcel shelf, unplugged it and noise went away, had it replaced under warranty.
Edit - just realized you said rear sub in title, that is the center one I believe in the parcel shelf, so one I had issues with, try unplugging and see.
Can you trace it to a speaker or corner of the car, I had one go bad in my 2013 crackling noise, was the center one in the parcel shelf, unplugged it and noise went away, had it replaced under warranty.
Edit - just realized you said rear sub in title, that is the center one I believe in the parcel shelf, so one I had issues with, try unplugging and see.
Last edited by roadkillrob; Apr 18, 2020 at 04:02 PM.
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Joined: Jul 2018
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09 C63 AMG
I had a similar issue, found the small rubber push pins that hold the black plastic molding along the edges of the truck seal were old and leaking slightly!! On the drivers side its directly above the amp main electrical plug... when I finally found it, small drops of water were landing directly into it causing a short and actually turned a few prongs green.. replaced the push pins and cleaned the connector and problem solved... could be a place to look as well
Thread Starter
Senior Member
Joined: Feb 2018
Posts: 339
Likes: 108
From: Virginia USA
2016 GTs, 2014 C63 AMG and 2014 C350 Sport (wife's car, she thinks it's an AMG - shhhhhh)
Cool thanks guys. I'll remove the rear shelf and start fiddling. You gave me a pace to start.
I'll update once I find the culprit.
I'll update once I find the culprit.
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Joined: Apr 2019
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From: Minnesota
09 C63 AMG
Tracing the source of the problem will be dependent on the symptom; is it the sub crackling or are the sub mounts loose causing the sub to rattle?
If the sub is crackling as you adjust signal settings on the HU as well as when the HU is off, and it is intermittent, I wouldn't rule out the amplifier as the source of the issue versus the driver. It is *possible* for something to have gone wrong internally over time with hot/cold cycles, vibration, etc.
Can easily test this at the amplifier outputs with a simple DMM (or more preferably a handheld O-scope). In your case, either a known signal (30Hz - 100Hz) or no signal while manipulating the HU and see how the signal output from the amp to the sub reacts. To eliminate the sub as the culprit, unplug the driver while testing, and also meter it.
Just some initial thoughts. Let me know if you have any questions. Good luck!
If the sub is crackling as you adjust signal settings on the HU as well as when the HU is off, and it is intermittent, I wouldn't rule out the amplifier as the source of the issue versus the driver. It is *possible* for something to have gone wrong internally over time with hot/cold cycles, vibration, etc.
Can easily test this at the amplifier outputs with a simple DMM (or more preferably a handheld O-scope). In your case, either a known signal (30Hz - 100Hz) or no signal while manipulating the HU and see how the signal output from the amp to the sub reacts. To eliminate the sub as the culprit, unplug the driver while testing, and also meter it.
Just some initial thoughts. Let me know if you have any questions. Good luck!
